Security Issues related to Apache servers and PHP

I\'m trying to get some information about setting up PHP on a Apache web server. My problem is mainly security because I won\'t be the only person on the server and the admin won\'t install PHP for me because he believes there is a security risk that I could (or anyone else using php) delete modify files in the other users web pages and this naturally is not allowed.

I was wondering if anyone had any documentation on setting php up for web servers with multiple users eg. can only edit files in eg. /web/username else do a command like: die(\'you are not authorized to do this action\')